SEOUL — It’s a mountain resort with a difference. Visitors to North Korea’s Mount Kumgang can revel in the beauty of scenic valleys, waterfalls and temples just a few miles from the heavily militarized border that divides the Korean Peninsula.

At least, that’s how the thinking went. Opened in 1999 and envisioned by North Korea as a destination for foreign tourists, especially South Koreans, the resort became a symbol of cross-border engagement amid often-fraught relations.

Families separated by the Korean War held reunions there. South Korean firms invested hundreds of millions of dollars in the project. But since the South pulled out in 2008, after one of its citizens was killed by a North Korean soldier, the resort has languished as a virtual ghost town.

On Wednesday, North Korean leader Kim Jong Un instructed officials to remove “shabby” and “unpleasant-looking” South Korean facilities from Mount Kumgang, state media reported.

He bemoaned the “very backward” South Korean architecture that resembled “makeshift tents in a disaster-stricken area.” North Korea should take the lead in developing the area according to “our own way,” Kim said, while stressing that South Koreans were still welcome to visit.

Security analysts said Kim’s move signaled his frustration at the lack of progress in proposed economic projects between North and South Korea, which are blocked by sanctions amid a deadlock in nuclear talks with Washington.

When South Korean President Moon Jae-in met with Kim in September last year, he agreed to resume cooperation on suspended projects, notably Mount Kumgang and a joint industrial park at Kaesong — valuable income sources for the cash-strapped North.

While tighter sanctions on Pyongyang since 2016 prohibited such ventures, hopes were high among business and political officials that improving relations might lead to sanctions relief. In a speech Jan. 1, the North Korean leader said he would resume operations in the resort and the industrial estate “without any preconditions.”

President Trump — a real estate investor himself — has talked up North Korea’s potential as a destination for tourists and tourism investment. He has even praised the appealing North Korean landscape seen in footage of the country’s missile tests.

“You could have the best hotels in the world right there,” he said after his first summit meeting with Kim in Singapore last year, where he assured North Korea of a “bright future” if it agreed to relinquish its nuclear weapons.

More than a year later, these business partnerships have not restarted, and a breakthrough in nuclear diplomacy with Washington seems increasingly elusive.

Rachel Minyoung Lee, an analyst with the North Korea-focused website NK News, said the change in Kim’s message indicates his regime “has decided it can no longer wait for South Korea to take action.”

“North Korea is basically telling South Korea that it will remove its installations and that, if [Seoul] wants to keep its share of the investment, it should act quickly” to resume economic cooperation, she said.

South Korea would seek to “protect the property rights of our people” and was willing to discuss the Mount Kumgang operations with North Korea, said Unification Ministry spokesman Lee Sang-min.

The flap over the resort, which is also known as Diamond Mountain, underscores the risks South Korean firms face in getting involved in ostensibly political projects with North Korea. While some see a prospective opening up of North Korea as a huge opportunity, many have suffered losses when relations have deteriorated in the past, and had their assets confiscated.

Hyundai Asan, a subsidiary of the Hyundai conglomerate that built and operated tourist accommodations around Mount Kumgang, said in a statement that the company was “confused” by North Korea’s announcement and would respond “in a calm manner.”

The company had been preparing to resume operations for years and had stepped up those measures as relations between North and South Korea warmed last year, said spokesman Kim Ha-young. Hyundai Asan said it had invested almost $200 million in facilities and paid some $480 million in operating fees to North Korea between 1999 and 2008.

In a budget speech on Tuesday, President Moon called for more economic engagement with North Korea, including a rail connection across the border. Moon said North Korea’s “bright future” is only possible on the basis of “peace economy” led by inter-Korean exchanges. “I urge North Korea to reciprocate,” he said.